Novel acaricidal and growth-regulating activity of Aloe vera and Rheum rhabarbarum extracts and their oil/water nanoemulsions against the camel tick, Hyalomma dromedarii.

Hyalomma dromedarii is an important tick species infesting livestock. This work evaluated the novel adulticidal, insect growth-regulating, and enzymatic efficacy of ethanol plant extracts of Aloe vera and Rheum rhabarbarum and their nanoemulsions against males and engorged females of the camel tick, H. dromedarii. The physicochemical properties of nanoemulsions were evaluated. The High-Performance Liquid Chromatography (HPLC) analyses indicated that the extracts contained polyphenols and flavonoids, which could enhance their acaricidal effect. Dynamic light scattering (DLS) of the nanoemulsions of A. vera and R. rhabarbarum were 196.7 and 291 nm, whereas their zeta potentials were - 29.1 and - 53.1 mV, respectively. Transmission electron microscope (TEM) indicated that nanoemulsions showed a regular spherical shape (less than 100 nm). Fifteen days post-treatment (PT) with 25%, the mortality% of A. vera and R. rhabarbarum were 88.5 and 96.2%, respectively. Five days PT, the median lethal concentration values of A. vera, R. rhabarbarum, and their nanoemulsions were 7.8, 7.1, 2.8, and 1.02%, respectively, and their toxicity indices were 91.02, 100, 36.4, and 100%, respectively. Their median lethal time values PT with 3.5% were 6.09, 5.09, 1.75, and 1.34 days, respectively. Nanoemulsions enhanced the efficacy of the crude extract 1-7 folds, 5 days PT, and accelerated their speed of killing ticks 2-4 times. The total protein and carbohydrates, Acetylcholinesterase, Alpha esterase, and Amylase were affected PT. The reproductive potential of engorged females was adversely impacted. In conclusion, the novel A. vera and R. rhabarbarum extracts were promising acaricides, and their nanoformulations enhanced their efficacies.

LC/HRESI-MS/MS screening, phytochemical characterization, and in vitro antioxidant and cytotoxic potential of Jatropha integerrima Jacq. extracts.

Avoiding the probable dangerous side effects of synthetic drugs, this study aims the identification of natural antioxidant and antitumor agents from J. integerrima leaf and floral extracts. A highly efficient and fast UPLC/ESI-qTOF-HRMS/MS screening has led to characterization of 30 flavonoids, i.e. 12 flavonols, 6 flavones, 3 dihydroflavonols, 4 anthocyanins (flower), 2 dihydroflavonols, and 3 isoflavones from both J. integerrima extracts. In addition, six major polyphenols were identified for the first time from leaf extract, and their structures were established as apigenin 7-O-ß-d-neohesperidoside (rhoifolin, 1), apigenin 8-C-ß-D-4C1-glucopyranoside (vitexin, 2), luteolin 6-C-ß-D-4C1-glucopyranoside (isoorientin, 3), 6,6″-di-C-ß-D-4C1-glucopyranosyl-methylene-biapigenin (Jatrophenol-I, 4), (E)-p-coumaric acid methyl ester (5), and (E)-ferulic acid methyl ester (6) with HRESI-MS and NMR analyses. The in vitro antioxidant activity of both extracts and major pure isolates was decided using DPPH, reducing power capability, FRAP, and ABTS radical scavenging assays, and their in vitro cytotoxicity was evaluated on Ehrlich ascites carcinoma cells (EACC), as well.The flower extract and compound 3 have shown the strongest antioxidant and cytotoxic effects. At low concentrations (25 µg/mL), they showed the highest DPPH radical scavenging ability (79.63 ± 0.42 and 76.20 ± 0.35%) regarding BHA (91.44 ± 0.29% at 100 µg/mL). In the parameter of absorbance, they exhibited higher reducing power ability (1.402 ± 0.025 and 1.178 ± 0.019%) than that of BHA (0.975 ± 0.013 at 100 µg/mL). Similarly, they proved superior FRAP (1427 ± 9.61 and 1377 ± 13.61 µmol Trolox/ 100 g) and highest ABTS activity (80.19 ± 0.55 and 68.38 ± 0.19%), which are higher activities compared to BHA (88.42 ± 0.24% at 100 µg/mL). Furthermore, all samples gave noticeable cytotoxicity at the same concentration (100 µg/mL), especially the flower extract and compound 3 which showed a relatively high effect on the viability of EACC (81.12 ± 0.24 and 77.21 ± 0.76 %, respectively) relative to vincristine reference drug (90.64 ± 0.39 %). Based on the findings, the extracts and isolates can be considered as potent antioxidant and cytotoxic natural agents, especially flower extract and isoorientin (3), which may supply novel insight into their likely application in pharmaceutical industries.

Antioxidant capacity and antitumor activity of the bioactive protein prepared from orange peel residues as a by-product using fungal protease.

Agricultural and industrial residues (AIR) are renewable biomass sources present in large quantities causing pollution. Converting AIR to eco-friendly products (bioactive materials) reduces their quantity and impact on the environment, in addition to reducing production costs. Therefore, orange peel (OP) protein degradation, antioxidant capacity, and antitumor activity were investigated using Aspergillus niger WA 2017 protease. The highest value of the protein hydrolysate with the highest antioxidant using the DPPH method was obtained after 24 h. The single-factor method boosted the protein hydrolysate and the DPPH antioxidant activity by 3.7 and 1.7-fold, respectively. Statistical optimized conditions (Central Composite Method) increased the hydrolysate value and the DPPH antioxidant activity by 1.6 and 1.1-fold, respectively. The central trial samples exhibited the highest DPPH antioxidant activity (62.37 %), while the control sample recorded 20 %. All antioxidant tests in vitro (DPPH, reducing power, ABTS, and FRAP) confirmed the superiority of the potent hydrolysate as a good antioxidant. In vitro antitumor activity, the potent hydrolysate exhibited the highest effect on the Ehrlich Ascites Carcinoma Cells viability as it recorded 60.62 % dead cells. In vivo antitumor activity, the volume of the untreated tumor mice was found to be 1.4-fold bigger than the volume obtained from the potent hydrolysate. The increase in life span (ILS %) for oral treatment and intraperitoneal injection treatment with the potent hydrolysate increased by 13.91 and 19.42 %, respectively, compared to the untreated tumor.

Safe production of Aspergillus terreus xylanase from Ricinus communis: gene identification, molecular docking, characterization, production of xylooligosaccharides, and its biological activities.

BACKGROUND: The production of industrial enzymes such as xylanase using sufficient cost-effective substrates from potent microorganisms is considered economically feasible. Studies have reported castor cake (Ricinus communis) as the most potent and inexpensive alternative carbon source for production of xylanase C by using Aspergillus terreus (A. terreus). RESULTS: A. terreus strain RGS Eg-NRC, a local isolate from agro-wastes, was first identified by sequencing the internal transcribed spacer region of a nuclear DNA encoding gene cluster deposited in GenBank (accession number MW282328). Before optimization of xylanase production, A. terreus produced 20.23 U/g of xylanase after 7 days using castor cake as a substrate in a solid-state fermentation (SSF) system that was employed to achieve ricin detoxification and stimulate xylanase production. Physicochemical parameters for the production of xylanase were optimized by using a one-variable-at-a-time approach and two statistical methods (two-level Plackett-Burman design and central composite design, CCD). The maximum xylanase yield after optimization was increased by 12.1-fold (245 U/g). A 60-70% saturation of ammonium sulfate resulted in partially purified xylanase with a specific activity of 3.9 IU/mg protein. At 60 °C and pH 6, the partially purified xylanase had the highest activity, and the activation energy (Ea) was 23.919 kJmol. Subsequently, antioxidant capacity and cytotoxicity tests in normal Ehrlich ascites carcinoma human cells demonstrated xylooligosaccharides produced by the xylanase degradation of xylan as a potent antioxidant and moderate antitumor agent. Further investigations with sodium dodecyl sulfate polyacrylamide gel electrophoresis then determined the molecular weight of partially purified xylanase C to be 36 kDa. Based on the conserved regions, observations revealed that xylanase C belonged to the glycosyl hydrolase family 10. Next, the xylanase-encoding gene (xynC), which has an open reading frame of 981 bp and encodes a protein with 326 amino acids, was isolated, sequenced, and submitted to the NCBI GenBank database (accession number LC595779.1). Molecular docking analysis finally revealed that Glu156, Glu262, and Lys75 residues were involved in the substrate-binding and protein-ligand interaction site of modeled xylanase, with a binding affinity of -8.7 kcal. mol-1. CONCLUSION: The high production of safe and efficient xylanase could be achieved using economical materials such as Ricinus communis.

Cardenolides and pentacyclic triterpenes isolated from Acokanthera oblongifolia leaves: their biological activities with molecular docking study.

Pentacyclic triterpenes and cardenolides were isolated from Acokanthera oblongifolia leaves. Their chemical structures were determined based on comprehensive 1D and 2D NMR spectroscopy. Their MIC was determined against 12 microorganisms. Their exerted cytotoxicity on the immortalized normal cells, hTERT-RPE1 was assessed by the sulforhodamine-B assay. The viral inhibitory effects of compounds against Newcastle disease virus (NDV) and H5N1 influenza virus IV were evaluated. Four in vitro antioxidant assays were performed in comparison with BHT and trolox and a weak activity was exhibited. Acovenoside A was with potent against H5N1-IV and NDV with IC50 ≤ 3.2 and ≤ 2.1 µg/ml and SI values of 93.75 and 95.23%, respectively, in comparison to ribavirin. Its CC50 record on Vero cells was > 400 and 200 µg/ml, respectively. Acobioside A was the most active compound against a broad range of microbes while Pseudomonas aeruginosa was the most sensitive. Its MIC (0.07 µg/ml) was 1/100-fold of the recorded CC50 (7.1 µg/ml/72 h) against hTERT-RPE1. The molecular docking of compounds on human DNA topoisomerase I (Top1-DNA) and IV glycoprotein hemagglutinin were studied using MOE program. This study has introduced the cardenolides rather than triterpenoids with the best docking score and binding interaction with the active site of the studied proteins.

Polyamines modulate growth, antioxidant activity, and genomic DNA in heavy metal-stressed wheat plant.

A pot experiment was performed to assess the useful effects of seed soaking or seedling foliar spray using 0.25 mM spermine (Spm), 0.50 mM spermidine (Spd), or 1 mM putrescine (Put) on heavy metal tolerance in wheat plants irrigated with water contaminated by cadmium (2 mM Cd2+ in CdCl2) or lead (2 mM Pb2+ in PbCl2). Cd2+ or Pb2+ presence in the growth medium resulted in significant reductions in growth and yield characteristics and activities of leaf peroxidase (POD), glutathione reductase (GR), ascorbic acid oxidase (AAO), and polyphenol oxidase (PPO) of wheat plants. In contrast, significant increases were observed for Cd2+ content in roots, leaves and grains, superoxide dismutase (SOD) and catalase (CAT) activities, radical scavenging activity (DPPH), reducing power capacity, and fragmentation in DNA in comparison to controls (without Cd2+ or Pb2+ addition). However, treating the Cd2+- or Pb2+-stressed wheat plants with Spm, Spd, or Put, either by seed soaking or foliar spray, significantly improved growth and yield characteristics and activities of POD, GR, AAO, PPO, SOD, and CAT, DPPH, and reducing power capacity in wheat plants. In contrast, Cd2+ levels in roots, leaves, and yielded grains, and fragmentation in DNA were significantly reduced compared with the stressed (with Cd2+ or Pb2+) controls. Generally, seed soaking treatments were more effective than foliar spray treatments. More specifically, seed priming in Put was the best treatment under heavy metal stress. Results of this study recommend using polyamines, especially Put, as seed soaking to relieve the adverse effects of heavy metals in wheat plants.

Levansucrase optimization using solid state fermentation and levan biological activities studies.

Bacillus subtilis NRC1aza produced levansucrase under solid state fermentation using starch as support. A sequential optimization strategy, based on statistical experimental designs is employed to enhance enzyme productivity. First, a 2-level Plackett-Burman design was applied for bioprocess parameters screen that significantly increase levansucrase production. Second optimization step was performed using fractional factorial design in order to optimize the amounts of highest positive variables that had significant effect on levansucrase productivity. Maximal enzyme productivity of 170 U/gds was achieved in presence of glucose, yeast extract, and pH 8. In vitro, experiments confirmed that LevCR and LevQT had an antitumor activity against different animal and human cancer cell lines by demonstrating inhibitory effects on growth of Ehrlich ascites carcinoma cell line, human MCF-7 breast and liver HepG2 cancer cell lines, in particular LevQT was found to be efficacious compared to anticancer drug, cisplatin. Result focused in LevCR as strong fibrinolytic agent.